scholarly journals Advanced Functional Tumor Imaging and Precision Nuclear Medicine Enabled by Digital PET Technologies

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Chadwick L. Wright ◽  
Katherine Binzel ◽  
Jun Zhang ◽  
Michael V. Knopp
Keyword(s):  
Nuclear Medicine ◽  
Tumor Imaging ◽  
Photon Counting ◽  
High Definition ◽  
Current Standard ◽  
Digital Detector ◽  
Timing Resolution ◽  
Technological Advances ◽  
Digital Pet ◽  
Digital Photon Counting

The purpose of this article is to provide a brief overview of the background, basic principles, technological evolution, clinical capabilities, and future directions for functional tumor imaging as PET evolves from the conventional photomultiplier tube-based platform into a fully digital detector acquisition platform. The recent introduction of solid-state digital photon counting PET detector is the latest evolution of clinical PET which enables faster time-of-flight timing resolution that leads to more precise localization of the annihilation events and further contributes to reduction in partial volume and thus makes high definition and ultrahigh definition PET imaging feasible with current standard acquisition procedures. The technological advances of digital PET can be further leveraged by optimizing many of the acquisition and reconstruction methodologies to achieve faster image acquisition to improve cancer patient throughput, lower patient dose in accordance with ALARA, and improved quantitative accuracy to enable biomarker capability. Digital PET technology will advance molecular imaging capabilities beyond oncology and enable Precision Nuclear Medicine.

Patients with fever of unknown origin (FUO): diagnosis by nuclear medicine imaging

2001 ◽  
Vol 40 (03) ◽  
pp. 59-70 ◽  
Author(s):  
W. Becker ◽  
J. Meiler
Keyword(s):  
Nuclear Medicine ◽  
Fever Of Unknown Origin ◽  
Tumor Imaging ◽  
White Blood Cells ◽  
Unknown Origin ◽  
Final Diagnosis ◽  
Recurrent Fever ◽  
Nuclear Medicine Imaging

SummaryFever of unknown origin (FUO) in immunocompetent and non neutropenic patients is defined as recurrent fever of 38,3° C or greater, lasting 2-3 weeks or longer, and undiagnosed after 1 week of appropriate evaluation. The underlying diseases of FUO are numerous and infection accounts for only 20-40% of them. The majority of FUO-patients have autoimmunity and collagen vascular disease and neoplasm, which are responsible for about 50-60% of all cases. In this respect FOU in its classical definition is clearly separated from postoperative and neutropenic fever where inflammation and infection are more common. Although methods that use in-vitro or in-vivo labeled white blood cells (WBCs) have a high diagnostic accuracy in the detection and exclusion of granulocytic pathology, they are only of limited value in FUO-patients in establishing the final diagnosis due to the low prevalence of purulent processes in this collective. WBCs are more suited in evaluation of the focus in occult sepsis. Ga-67 citrate is the only commercially available gamma emitter which images acute, chronic, granulomatous and autoimmune inflammation and also various malignant diseases. Therefore Ga-67 citrate is currently considered to be the tracer of choice in the diagnostic work-up of FUO. The number of Ga-67-scans contributing to the final diagnosis was found to be higher outside Germany than it has been reported for labeled WBCs. F-l 8-2’-deoxy-2-fluoro-D-glucose (FDG) has been used extensively for tumor imaging with PET. Inflammatory processes accumulate the tracer by similar mechanisms. First results of FDG imaging demonstrated, that FDG may be superior to other nuclear medicine imaging modalities which may be explained by the preferable tracer kinetics of the small F-l 8-FDG molecule and by a better spatial resolution of coincidence imaging in comparison to a conventional gamma camera.

scholarly journals Fully digital PET is unaffected by any deterioration in TOF resolution and TOF image quality in the wide range of routine PET count rates

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Julien Salvadori ◽  
Freddy Odille ◽  
Gilles Karcher ◽  
Pierre-Yves Marie ◽  
Laetitia Imbert
Keyword(s):  
Image Quality ◽  
Dead Time ◽  
Silicon Photomultipliers ◽  
Timing Resolution ◽  
Upper Limits ◽  
Wide Range ◽  
Pile Up ◽  
Digital Pet ◽  
Trigger Circuit

Abstract Purpose Digital PET involving silicon photomultipliers (SiPM) provides an enhanced time-of-flight (TOF) resolution as compared with photomultiplier (PMT)-based PET, but also a better prevention of the count-related rises in dead time and pile-up effects mainly due to smaller trigger domains (i.e., the detection surfaces associated with each trigger circuit). This study aimed to determine whether this latter property could help prevent against deteriorations in TOF resolution and TOF image quality in the wide range of PET count rates documented in clinical routine. Methods Variations, according to count rates, in timing resolution and in TOF-related enhancement of the quality of phantom images were compared between the first fully digital PET (Vereos) and a PMT-based PET (Ingenuity). Single-count rate values were additionally extracted from the list-mode data of routine analog- and digital-PET exams at each 500-ms interval, in order to determine the ranges of routine PET count rates. Results Routine PET count rates were lower for the Vereos than for the Ingenuity. For Ingenuity, the upper limits were estimated at approximately 21.7 and 33.2 Mcps after injection of respectively 3 and 5 MBq.kg-1 of current 18F-labeled tracers. At 5.8 Mcps, corresponding to the lower limit of the routine count rates documented with the Ingenuity, timing resolutions provided by the scatter phantom were 326 and 621 ps for Vereos and Ingenuity, respectively. At higher count rates, timing resolution was remarkably stable for Vereos but exhibited a progressive deterioration for Ingenuity, respectively reaching 732 and 847 ps at the upper limits of 21.7 and 33.2 Mcps. The averaged TOF-related gain in signal/noise ratio was stable at approximately 2 for Vereos but decreased from 1.36 at 5.8 Mcps to 1.14 and 1.00 at respectively 21.7 and 33.2 Mcps for Ingenuity. Conclusion Contrary to the Ingenuity PMT-based PET, the Vereos fully digital PET is unaffected by any deterioration in TOF resolution and consequently, in the quality of TOF images, in the wide range of routine PET count rates. This advantage is even more striking with higher count-rates for which the preferential use of digital PET should be further recommended (i.e., dynamic PET recording, higher injected activities).

High Rate Photon Counting CT Using Parallel Digital PET Electronics

2007 ◽  
Author(s):  
Joel Riendeau ◽  
Philippe Berard ◽  
Nicolas Viscogliosi ◽  
Marc-Andre Tetrault ◽  
Francois Lemieux ◽  
...  
Keyword(s):  
Photon Counting ◽  
High Rate ◽  
Digital Pet

scholarly journals 3D Laparoscopic Monitors

2014 ◽  
Vol 5 ◽  
pp. MEI.S13342
Author(s):  
Francesca Destro ◽  
Noemi Cantone ◽  
Mario Lima
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Three Dimensional ◽  
Short Paper ◽  
High Definition ◽  
Recent Introduction ◽  
Technological Advances ◽  
New Surgery

Minimally invasive surgery (MIS) is a relatively new surgery comprising various procedures performed with special miniaturized instruments and imaging reproduction systems. Technological advances have made MIS an efficient, safe, and applicable tool for pediatric surgeons with unquestionable advantages. The recent introduction of three-dimensional (3D) high definition systems has been advocated in order to overcome some of the problems related to standard MIS visual limitations. This short paper recapitulates the necessity to minimize MIS visualization limitations and reports the characteristics of new laparoscopic 3D systems.

scholarly journals The Downside of Radiosurgery, Possible Complications

2018 ◽  
Vol 25 (3) ◽  
pp. 286-299
Author(s):  
Luiz Claudio Modesto Pereira ◽  
Valeria Patricia De Araujo ◽  
Thiago Henrique de Moraes Modesto
Keyword(s):  
Tumor Imaging ◽  
Neurological Complications ◽  
Normal Brain ◽  
Radiation Delivery ◽  
Cranial Nerve Dysfunction ◽  
Technological Advances ◽  
Treatment Dose ◽  
Barrier Breakdown ◽  
Nerve Dysfunction ◽  
Blood Brain Barrier Breakdown

As a consequence of various last century scientific and technological advances radiotherapy and stereotactic radiosurgery (SRS) have emerged as safe and efficacious techniques for the treatment of various intracranial pathologies. Recent improvements such as in brain and tumor imaging, patient immobilization, 3D planning and radiation delivery allow it to target lesions more accurately and minimize radiation delivered to normal brain, leading to drastic improvements in terms of safety and post-therapy complication. Despite that SRS still implies in moderate to severe side effects in one fifth to one fourth of patients. Fortunately the most common SRS complications, such as edema, blood brain barrier breakdown and MRI abnormalities are self-limited and amenable to treatment. The precise pathophysiological processes of SRS complications are still under research, however multiple factors including treatment dose, modality and planning complexity, target size, shape and location are known to affect treatment results. The most reported potential SRS complications are ischemic stroke, brain or lesion hemorrhage, radiosurgeryinduced neoplasm, radiation necrosis, white matter changes, cranial nerve dysfunction and cognition problems. SRS induced neurological complications may persist only in as much as 5% of patients.

scholarly journals High-resolution underwater laser spectrometer sensing provides new insights into methane distribution at an Arctic seepage site

Ocean Science ◽  
2019 ◽  
Vol 15 (4) ◽  
pp. 1055-1069 ◽  
Author(s):  
Pär Jansson ◽  
Jack Triest ◽  
Roberto Grilli ◽  
Bénédicte Ferré ◽  
Anna Silyakova ◽  
...  
Keyword(s):  
High Resolution ◽  
Water Column ◽  
Numerical Models ◽  
Fast Response ◽  
Laser Spectrometer ◽  
Current Standard ◽  
Discrete Sampling ◽  
Mixing Ratios ◽  
Technological Advances ◽  
Ocean Measurements

Abstract. Methane (CH4) in marine sediments has the potential to contribute to changes in the ocean and climate system. Physical and biochemical processes that are difficult to quantify with current standard methods such as acoustic surveys and discrete sampling govern the distribution of dissolved CH4 in oceans and lakes. Detailed observations of aquatic CH4 concentrations are required for a better understanding of CH4 dynamics in the water column, how it can affect lake and ocean acidification, the chemosynthetic ecosystem, and mixing ratios of atmospheric climate gases. Here we present pioneering high-resolution in situ measurements of dissolved CH4 throughout the water column over a 400 m deep CH4 seepage area at the continental slope west of Svalbard. A new fast-response underwater membrane-inlet laser spectrometer sensor demonstrates technological advances and breakthroughs for ocean measurements. We reveal decametre-scale variations in dissolved CH4 concentrations over the CH4 seepage zone. Previous studies could not resolve such heterogeneity in the area, assumed a smoother distribution, and therefore lacked both details on and insights into ongoing processes. We show good repeatability of the instrument measurements, which are also in agreement with discrete sampling. New numerical models, based on acoustically evidenced free gas emissions from the seafloor, support the observed heterogeneity and CH4 inventory. We identified sources of CH4, undetectable with echo sounder, and rapid diffusion of dissolved CH4 away from the sources. Results from the continuous ocean laser-spectrometer measurements, supported by modelling, improve our understanding of CH4 fluxes and related physical processes over Arctic CH4 degassing regions.

Digital, photon-counting fluorescence polarometer

1976 ◽  
Vol 48 (6) ◽  
pp. 846-856 ◽  
Author(s):  
R. J. Kelly ◽  
W. B. Dandliker ◽  
Donald E. Williamson
Keyword(s):  
Photon Counting ◽  
Digital Photon Counting

scholarly journals Towards digital photon counting cameras for single-molecule optical nanoscopy

2014 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
Venkataraman Krishnaswami ◽  
Cornelis J F Van Noorden ◽  
Erik M M Manders ◽  
Ron A Hoebe
Keyword(s):  
Single Molecule ◽  
Photon Counting ◽  
Digital Photon Counting
Sign in / Sign up

Export Citation Format

Share Document